Every year there are fewer "brick-and-mortar" retailers. Not coincidentally, there are ever more online retailers.
The question is: where's the best place to buy an HDTV?
Generally speaking, online is going to be cheaper. Some stores will match the pricing for exact models, but not all. If you know the TV you're looking at is X, and the store has it for X+$50, it's worth asking to see if they'll match it. Smarter retailers would rather have a less profit than no profit. Others will bid you on your way. No harm in asking.
Bottom line: Online, but worth asking about
Obvious answer is obvious. Online is effectively infinite. That said, the big retailers like Best Buy and Costco are going to carry all the most popular models of the big brands. So unless you're looking for some off-brand or weird size, chances are you'll find what you need in a store.
Bottom line: Wash
If you're not exactly sure what TV you want, and hope to decide by looking at them, surprisingly a store doesn't offer much more in this regard than online.
Every big retailer has lighting radically different from your home. You're also not likely to be standing at the normal viewing distance.
Checking out a few of my local stores, I found some models a few inches on the floor, others way over my head. Some rows I was forced to be just a couple of feet away, others I had to step back to see the TV. All of these factors change your perception the TV. Worse, if you're trying to compare two TVs, and one is by your feet, and the other is over your head, how do you compare?
In perhaps the best example I can think of for the futility of in-store evaluation, a TV I knew to be good, placed knee-level in a narrow corridor, looked noisy and overall terrible. I'd reviewed the thing and even I wouldn't buy it if all I'd seen was its in-store performance. Conversely, a TV I knew to be highly mediocre, was given center stage, its backlight cranked all the way up, giving it the appearance of being special.
Some smaller retailers may have darkened show floors, which is slightly better to judge.
My advice: do your research beforehand, then judge the TV at home (given a reasonable return policy). If the TV is well-reviewed, and other consumers have positive things to say, and it looks good in your home, guess what? You've picked a fantastic television.
Bottom Line: slight edge toward in-store...maybe
As long as the TV isn't too big, or you've got a big truck, you can drive it home. That's the biggest advantage to in-store: instant gratification. Most stores will charge you to deliver it, but specials come along with free shipping.
Online depends on the site. Amazon.com offers free shipping on a lot of TVs, and if you subscribe to its Prime service, two-day shipping on everything is free..
Bottom line: About a wash
Well, it's hard to beat driving a TV back to the store and telling them where they can stick it (in their warehouse; what did you think I meant?). Most retailers have 30-day no-questions-asked return policies. Some have shortened this to 15 days, and some even have a restocking fee. Definitely worth checking out ahead of time. Costco has a pretty liberal return policy (90 days on TVs), if you're a member.
Online varies a lot. If you buy from Amazon, it has a 30-day return policy with free return shipping. Be careful, though, as Amazon isn't always Amazon. Many retailers use Amazon as a vehicle to sell their own wares. In these cases, Amazon is merely a facilitator. As in, you pay Amazon, but you actually bought the TV from Tim's Terrible TV Trader. Its return policy could be anything. So check the fine print. There's a middle ground, where it's "Fulfillment by Amazon" in which the stock may come from Random Ricky's Retailer, but Amazon takes responsibility.
Bottom Line: Varies, a lot. Check before buying
Costco extends the manufacturer's warranty on TVs to two years. All stores, virtual or physical, will offer extended warranties.
Your credit card may offer an extension of the manufacturers' warranty. Certain AmEx and Visa cards often offer this.
It's worth noting that plasma and LCD TVs have proven to be very reliable. Extended warranties are usually not worth purchasing. Check out How long do TVs last? for more info.
Bottom Line: Costco, I guess. If it really worries you, get an extended warranty (though they're rarely worth it).
Support Well, good luck. It's not likely you'll get much support in any fashion from any retailer, really. Some will offer in-home setup, though the quality of this is dubious at best. I've heard stories of HDTVs being hooked up with composite cable (which can't do HD, 480i only).
Some retailers offer pay services that will hook up the TV for you, but these aren't much better sometimes.
Specialty retailers and custom installers usually have the know-how and are in the business of high-tech setup and installation, but this knowledge and skill comes at a price.
If you're not a do-it-yourselfer, check out my article on HDTV calibration for options.
Bottom line: You're on your own, unless you want to pay
Even though our tally shows a fairly even balance, I think it's fair to weigh selection and price heavier than the others. So with that in mind, online is a decided winner. If you're careful to note return policies and warranty availability, buying online is an excellent option. The better online retailers (and some are definitely better than others) will almost always have better prices and a wider selection.
Buying in a store certainly offers that instant gratification and the touchy-feely aspect a computer screen can't mimic (yet), but given the perils of in-store evaluation (as noted above) this hands-on aspect is largely of little use.
What do you think? Would you buy a TV online? Would you never?
But do me a favor
I worked in retail for a number of years. Best Buy, Costco, etc., have effectively become the retail salesfloor for Amazon.com. People come in, check out the TV they want (see above!) then buy it online. So it goes.
But if you find a smaller, specialty retailer that actually offers a decent place to view the TV you want to buy... please be honest about your intentions. Don't waste someone's time, as chances are the smaller stores have salespeople paid on commission. As they patiently answer all of your questions, just for you to bail, they've potentially lost money not being able to help someone who is going to buy. So you've effectively cost them money by wasting their time.
It also makes you a jerk.
So be honest, tell them you're probably not going to buy. Maybe they'll have a special deal to lure you into buying it there and then. They're not going to kick you out of the store, paint a big red "A" on your chest, or stone you if you tell them you're not buying. If they're smart (and not busy), they'll probably help you anyway, because that's good for future business.
Got a question for Geoff? Send him an e-mail! If it's witty, amusing, and/or a good question, you may just see it in a post just like this one. No, he won't tell you which TV to buy. Yes, he'll probably truncate and/or clean up your e-mail. You can also send him a message on Twitter: @TechWriterGeoff.